HELP!! Corrupt .wav files cannot be opened

[Reed Gidez]

I recorded a few interviews this afternoon using my usually trusty Marantz PMD620. Of the 8 files created, 3 cannot be opened. I tried to play them on the recorder and I get an "err format1" message. Called Marantz professional support and they told me to send the card out for file recovery.

The icons for these three files show up as .wav on my Mac Pro but are different than the 'standard' wav icons (white with black musical note vs. opposite for ok files)

I've tried Disk Warrior and Stellar file recovery but so far no luck. Does anyone have any suggestions or has anyone been in this situation before?

Thanks in advance.

Reed

[Reed Gidez]

I was able to open the rogue files by importing them as raw files into Audacity. They were recorded with the PCM-24 setting on the Marantz at 48kHz. I imported using these same parameters and selected the "big endian" setting (??)

The files were playable albeit with a fair amount of hiss, not present in the other files recorded. This tells me the workflow is close to the mark however where is this noise coming from? Is there a better option to import the files as "raw"?

Thanks in advance for any help offered.

Reed

[Gary Nattrass]

Have you had an OSX update recently as sometime an update can suddenly cause a spanner in the works, it may be worth re-installing quicktime.

I had a big problem with final cut crashing recently and re-installing the OSX and quicktime cured it.

[Reed Gidez]

Gary

Thanks for the suggestion though I'm fairly certain the files were corrupted in the recorder. After the interviews, I went back to my studio and plugged in the recorder to USB to download the files from the card. The recorder said it was connecting via USB but it never showed up on the desktop. I unplugged the recorder, powered down, and removed the SD card and used my card reader.

Today's mission is to clean up the files as best as possible.

Reed

[Gary Nattrass]

Do you always re-format the cards in the recorder before each use as just erasing previous files can cause problems as it does not initialise the card directory structure.

Also re-formatting should log any bad memory blocks although that is more prevalent on hard discs rather than flash memory cards.

Also make sure your recorder firmware is up to date as some of the marantz recorders had software bugs and that can cause problems.

Finally make sure you are using recommended cards or decent media as cheaper lower speed cards can cause problems too.

I have the older PMD670M and only use Sandisk Extreme III cards with it.

[Reed Gidez]

All good info Gary. Thank you. I am generally a stickler when it comes to firmware updates but I don't regularly reformat cards. The card is a Kingston SDHC class 4 card. Never had issues in the past BUT I went through a slew of bad Kingston CF cards a while back and Kingston did recognize that had a bad controller on a whole series of cards. Haven't purchased any since but I think I may retire this particular one. SDs are relatively cheap these days anyway.

[Gary Nattrass]

They do go off in time as bad sectors can get corrupted but re-formatting before each use will cut down errors, as you say they are cheap as chips these days and it would be good practice to replce them every two years if they are used a lot.

Drivers for card readers can also get updated and make older cards obsolete.

[Roberto Diaz]

Originally Posted by Reed Gidez

selected the "big endian" setting (??)

"big endian" and "little endian" are computer terms referring to how data bytes are stored on memory cards, hard drives, etc.

those media use 8-bit data bytes. when your sampled audio is captured at 12 or 16 bits, each sample takes two 8-bit bytes, and those two bytes can be stored in two different ways (first-then-second or second-then-first). and that's what the "endian" terms refer to... the order the bytes were written.

now a recorder or computer or whatever always writes them in the same order, but one device might use one order and another device a different order. the order isn't really important but it's important that they're read back in the same order as they were written.

fortunately, if you get in the situation where you have to specify the "endian" manually, just try one then the other because the wrong one will sound like static/hiss.

hope that wasn't too technical.

[Reed Gidez]

Hey Roberto

Thanks for the explanation. I nearly blew out my monitors with the wrong endian settings before I figured it out. Just wish there was a way to recover the audio without the 'hiss'. The other recordings were quite good and my audio sweetening skills are limited at best. I was able to make the clips work but it was tough getting to that point.

Many lessons learned on this episode!

Thanks again

[Greg Miller]

Do the playback levels look like what you'd expect, based on the levels while you were recording?

Any chance you could post a short sample (to keep the file size permissable)? No editing, no conversion to another format... just select a small part of the "hissy" file, export that in the exact same format, and post it.

[Reed Gidez]

Here is a clip made of one bad .wav converted through audacity and a sample from the same session that was not corrupt. Same levels, recorder, mic. Male voice is totally unprocessed except for knocking down the sample rate to 41,100 and bit rate to 16 to make file a little smaller for this forum. Both were recorded at 48k and 24 bit

Equipment was Marantz PMD 620 with a RODE Videomic Pro.

[Rick Reineke]

Perhaps I'm missing something here, but the file plays back fine and sounds ok. ???
That said, when I encounter audio files that won't play correctly, I change the extension <*.raw> and open in Sound Forge Pro. If it's salvageable, that usually will do it. If the file corrupt (ie; missing) or it's a card issue, there's not much that can be done.

[Gary Nattrass]

Yes there is a lot of background noise on the female voice, it sounds like quantisation noise and the recording must have been corrupted whist it was recorded.

It is probably that the number of samples doesn't match the directory marker and that could be caused by a corrupted directory on the card.

[Reed Gidez]

Originally Posted by Rick Reineke

Perhaps I'm missing something here, but the file plays back fine and sounds ok. ???
That said, when I encounter audio files that won't play correctly, I change the extension <*.raw> and open in Sound Forge Pro. If it's salvageable, that usually will do it. If the file corrupt (ie; missing) or it's a card issue, there's not much that can be done.

Rick, the file is actually bits of two separate files recorded during the same session. The female voice was one of the corrupted .wav files that I managed to somewhat salvage (see earlier post in this thread).

Is is usually the case with technical glitches, I ended up learning a some workarounds and some new tricks to try in the future should I run up against this again.

Thank you all for suggestions and feedback!